Göran Ekström's main research interest is global earthquake seismology. This includes the detailed study of individual earthquake ruptures, and the relationship between seismicity and the large scale tectonic deformation of the crust and mantle over geologic time. Prof. Ekström's teaching interests include Environmental Geology, in particular the science and policy aspects of the assessment and mitigation of Geologic Hazards.

Gordon Jacoby Jr., a Columbia University researcher who hiked, flew, dove and paddled into some of the wildest corners on earth in search of trees that could reveal the planet’s workings, died on Oct. 1 at a hospital near his home in Raphine, Va. He was 80.

Most earthquakes erupt suddenly from faults near Earth’s surface, and the big ones can topple cities. But miles below, rocks heated to the consistency of wax moving over thousands to millions of years may be the driving force behind some of these events.

Large earthquakes from distant parts of the globe are setting off tremors around waste-fluid injection wells in the central United States, says a new study. Furthermore, such triggering of minor quakes by distant events could be precursors to larger events at sites where pressure from waste injection has pushed faults close to failure, say researchers.

A new study in the journal Nature provides fresh insight into deep-earth processes driving apart huge sections of the earth’s crust. The process, called rifting, mostly takes place on seabeds, but can be seen in a few places on land—nowhere more visibly than in the Afar region of northern Ethiopia. (See the slideshow below.) Here, earthquakes and volcanoes have rent the surface over some 30 million years, forming part of Africa’s Great Rift Valley. What causes this, and does it resemble the processes on the seafloor, as many geologists think?

Earthquakes that have shaken an area just outside Youngstown, Ohio in the last nine months—including a substantial one on New Year’s Eve—are likely linked to a disposal well for injecting wastewater used in the hydraulic fracturing process, say seismologists at Columbia University’s Lamont-Doherty Earth Observatory who were called in to study the quakes.

For all of its violent destruction, the earthquake that struck Haiti on Jan. 12, 2010, hardly scratched the surface of the island. But scientists now say they have found some of the best clues to understanding the quake under water.

After the recent great quakes that have swept away entire coastlines and cities in Japan, Haiti and Sumatra, scientists are now looking hard at the nation that may suffer the gravest threat of all: Bangladesh. A new documentary from the Earth Institute follows seismologists as they trace signs of deeply buried active faults, past movements of the earth, and sudden, catastrophic river-course changes.

Starting today, armchair explorers will be able to view parts of the deep ocean floors in far greater detail than ever before, thanks to a new synthesis of seafloor topography released through Google Earth. Developed by oceanographers at Columbia University’s Lamont-Doherty Earth Observatory from scientific data collected on research cruises, the new feature tightens resolution in covered areas from the former 1-kilometer grids to just 100 meters.

The recent earthquake in Japan shifted the earth’s axis by half a foot. You may be wondering if that’s enough to change earth’s weather. No, not really, says Jerry McManus, a climate scientist at Columbia’s Lamont-Doherty Earth Observatory.

The largest recorded earthquake in Japan's history has triggered a series of events that have killed thousands, crushed and submerged cities, and left a financial toll from which it will take years for an already struggling economy to recover.

Each year, dozens of small, mostly harmless earthquakes quakes rattle the northeastern United States and southern Canada, and one quite active area runs along the shores of lakes Erie and Ontario, in western New York. In order to learn more about what generates these, and the possible threat of something bigger, scientists at Columbia University’s Lamont-Doherty Earth Observatory have installed a new seismometer at the West Valley Central School, southeast of Buffalo.

In nature, random signals often fall mysteriously in step. Fireflies flashing sporadically in early evening soon flash together, and the same harmonic behavior can be seen in chirping crickets, firing neurons, swinging clock pendulums and now, it turns out, rupturing earthquake faults.

This week U.S. and Haitian scientists will start a 20-day research cruise off Haiti to address urgent questions about the workings of the great Jan. 12 earthquake, and the possibility of continuing threats. They hope to gather sonar images, sediments and other evidence from the seafloor that might reveal hidden structures...

The earthquake that struck Haiti took place along what is called a strike-slip fault—a place where tectonic plates on each side of a fault line are moving horizontally in opposite directions, like hands rubbing together. When these plates lock together, stress builds; eventually they slip; and this produces shaking.

That rumbling you feel is not necessarily a passing subway. New York City and the surrounding region gets a surprising number of small earthquakes, and a 2008 study from the region’s network of seismographs, run by Lamont-Doherty Earth Observatory, suggests that the risk of a damaging one is not negligible. This week, the federal government announced a major upgrade to that network.

Dec 10, 2007--Scientists from Columbia University’s Lamont-Doherty Earth Observatory will report this week on vital topics including new evidence of the effects of climate change; technologies to confront it; studies of eastern U.S. earthquake risk; and previously unseen inner workings of the deep polar ice caps. The reports will be presented at the fall 2007 American Geophysical Union (AGU), the largest earth-sciences gathering in the world, Dec. 10-14 in San Francisco.

Seismologists at Columbia University and Harvard University have found a new indicator that the Earth is warming: "glacial earthquakes" caused when the rivers of ice lurch unexpectedly and produce temblors as strong as magnitude 5.1 on the moment-magnitude scale, which is similar to the Richter scale. Glacial earthquakes in Greenland, the researchers found, are most common in July and August, and have more than doubled in number since 2002.

When the sea floor off the coast of Sumatra split on the morning of December 26, 2004, it took days to measure the full extent of the rupture. Recently, researchers at Columbia University's Lamont-Doherty Earth Observatory analyzed recordings of the underwater sound produced by the magnitude 9.3 earthquake.

The Maurice Ewing, owned by the National Science Foundation and operated by the Lamont-Doherty Earth Observatory (L-DEO), is the only research vessel devoted to obtaining images of the deep earth for fundamental earth science research.

Finding the epicenter of earthquakes has not changed in principle since the 1930s -- after closely examining seismograms from different widely-spaced listening stations, researchers decide on the arrival times of various seismic waves and calculate an approximation. In practice this can result in errors of several miles

Researchers have found an important new application for seismic reflection data, commonly used to image geological structures and explore for oil and gas. Recently published in the journal Nature, new use of reflection data may prove crucial to understanding the potential for mega earthquakes.